Yellow Dwarf Viruses: Aphid Transmission Efficiency and Cereal Host Range

Area of Science:

• Plant Virology
• Entomology
• Cereal Crop Science

Background:

• Yellow dwarf viruses (YDVs) significantly impact global cereal yields.
• Barley yellow dwarf virus PAV (BYDV PAV) is endemic in Australia, while barley virus G (BVG) and barley yellow dwarf virus PAS (BYDV PAS) are recent introductions.
• Limited data exists on BVG transmission and host range, particularly in Australia.

Purpose of the Study:

• To investigate the transmission efficiency of BVG, BYDV PAS, and BYDV PAV by four aphid species in Australia.
• To determine the host range of BVG.
• To provide epidemiological insights into YDV in Australian cereal crops.

Main Methods:

• Glasshouse experiments were conducted to assess aphid transmission efficiency.
• Four aphid species (bird cherry-oat, corn leaf, rose grain, and Russian wheat aphids) were tested.
• Host range experiments identified additional BVG hosts.

Main Results:

• BYDV PAS and BYDV PAV were transmitted effectively by all four aphid species.
• Corn leaf aphid showed significantly higher transmission rates for BVG (63%) compared to previous reports (7%).
• Bird cherry-oat aphid also transmitted BVG, though less efficiently. Russian wheat aphid did not transmit any tested YDVs. Four new BVG hosts were identified.

Conclusions:

• Corn leaf aphid is a highly efficient vector for BVG, with implications for disease spread.
• Aphid vector specificity influences YDV epidemiology.
• Findings enhance understanding of YDV-aphid-host interactions for improved crop management strategies.